Detection rules › Sublime MQL

Attachment: Excel Web Query File (IQY)

Severity
high
Type
rule
Source
github.com/sublime-security/sublime-rules

Recursively scans files and archives to detect IQY files. Coercing a target user into providing credentials to an attacker-controlled web server, or for SMB relaying.

Threat classification

Sublime's own taxonomy (not MITRE ATT&CK).

CategoryValues
Attack typesCredential Phishing, Malware/Ransomware
Tactics and techniquesEvasion

Event coverage

Rule body MQL

type.inbound
and (
  any(attachments, .file_extension =~ "iqy")
  or (
    any(attachments,
        .file_extension in~ $file_extensions_common_archives
        and any(file.explode(.), .file_extension =~ "iqy")
    )
  )
)

Detection logic

Scope: inbound message.

Recursively scans files and archives to detect IQY files. Coercing a target user into providing credentials to an attacker-controlled web server, or for SMB relaying.

  1. inbound message
  2. any of:
    • any of attachments where:
      • .file_extension is 'iqy'
    • any of attachments where all hold:
      • .file_extension in $file_extensions_common_archives
      • any of file.explode(.) where:
        • .file_extension is 'iqy'

Inspects: attachments[].file_extension, type.inbound. Sensors: file.explode. Reference lists: $file_extensions_common_archives.

Indicators matched (2)

FieldMatchValue
attachments[].file_extensionequalsiqy
file.explode(attachments[])[].file_extensionequalsiqy